Toy airplane and method of making the same



April 8, 1941. T. D. WILDON TOY AIRPLANE AND METHOD OF MAKING THE SAMEFiled Aug. 15, 1939 Patented Apr. 8, 1941 TOY AIRPLANE AND METHOD OFMAKING THE SAME.

Thomas D. Wilden, Reading, Mass., assigncr to Paul K. Guillow,

Wakefield, Mass.

Application August 15, 1939, Serial No. 290,227

(Cl. iii-78) 15 Claims.

The present invention is concerned with toy airplanes and its object isto produce such a toy simulating airplanes of the enclosed body type. Afurther object is to make such toy airplanes with adequate strength andrigidity out of a minimum number of parts and with efficiency andeconomy of manufacture.

The invention comprises both a method or procedure in the fabricationoftoy airplanes and novel features of construction and combination ofparts of such an airplane.

In the drawing illustrating the invention- Fig. 1 is a perspective viewof one form or embodiment thereof;

Fig. 2 is a perspective view of a out of which the bodies of the toyairplanes are made, illustrating one step of the procedure of makingthem;

Fig. 3 is a sectional view of the members of the toy airplane step ofproducing their lateral contours Fig. 4 is a perspective view of thepower plant of one embodiment of the invention, including also theexpander by which the molded formation of the body is achieved;

Fig. 5 is a perspective View containing the invention and illustratingthe step of expanding it to molded form;

Fig. 6 is a cross section taken on line 6-4: of Fi 5 and shown on alarger scale;

Fig. 7 is a horizontal longitudinal section through the body of a toyairplane containing theinvention and showing a form of power plantalternative to that shown in Fig. 1;

Fig. 8 is a cross section taken on line 3-8 of Fig. '7 on a scalesimilar to that of Fig. 6.

The body a of the airplane is constructed of two sheets of materialhaving suitable stiffness and elasticity, which is also capable of beingtreated so as to become pliable and of setting into the form imparted toit while in the pliable state. Balsa wood veneer has these properties,becoming very pliable when heated and wetted by steam and returning toits normal state of stifiness and elasticity after cooling and drying.Hence I prefer to use sheets of balsa wood veneer of a thicknessproportional to the other dimensions of the body. For toys in which thebody length is in the order of from 9" to 1, a thickness of veneerapproximating .045" to .050" is suitable; and other thicknesses inproportion are usable for planes of other dimensions. However, I wish itto be understood that this statement is not a limitation of theinvention either as to the material or as to its relative thickness, and

stack of pieces body connected together prior to the :2:

that I may use other known materials having like properties which arecapable of being formed in the manner described, and are sufiicientlylight in weight when formed in sheets thick enough to have requisitestrength.

In carrying out the method of molding the body, a pair of duplicateparts, each constituting one side of the body, are provided and are laidagainst one another with their edges coinciding. But preferably, inquantity production, a number of such pairs, identical in dimensions andoutline, are laid together in a stack as represented in Fig. 2. Theedges of the pieces so laid together in pairs, or stacked, are thenunited by a strongly adhesive and cohesive flexible connecting agent.Preferably a fluid cement capable'oi drying or setting into solid andwater-insoluble condition is used. Cellulose acetate dissolved in avolatile solvent, and other cellulose compounds in their known solvents,(together with a known emollient, such as castor oil, if necessary toprevent them from becoming brittle when dry) are suitable for thispurpose. Such I compositions, after drying, are exceedingly tough andare at 1.". the same time sufficiently flexible for my purposes of anairplane body when spread in films having the thickness of a singlecoating, such as are used here.

After drying of the cement, and after separation of the pairs of bodysides from one another, when a number of pairs have been cemented in astack, the members of each pair, as represented at b and c in Fig. 3,are connected by films d and e of cement adhering to their edges andcrossing the cleavage plane between them. These connected parts are thensteamed until thoroughly heated and moistened. This treatment makes thempliable and capable of being widely bent either with the grain or acrossthe grain without breaking or splitting.

While in the pliable state'the connected side sheets b and c are spreadapart by a wedge piece f (Fig. 55) inserted between them at the forwardend of the body and pushed toward the rear or tail end. The wedge pieceor spreader may have a straight continuous taper as shown in thedrawing, or a convex or concave taper. Its entering end is reducednearly or quite to a line edge and its butt end is given they widthprescribed for the forward end of the body, which may approximate theheight of the body at that end.

Insertion of the Wedge or spreader bulges out the sides of the body inapproximately their mid height, giving the body a molded shape withconvex external contours. It is allowed to remain in the body while thesaturated woodis dried.

When the body dries, it becomes set in its molded form which ispreserved by the stiffness of the material even though the spreader beremoved.

Wings g, h of monoplane type are assembled with the body by being passedthrough slots i in the side pieces, and a horizontal stabilizer vane kis set into a slot Z opening from the tail end of the body. These slotsare preferably cut simultaneously in a stack of blanks which have beenassembled as above described; although they may be made at any stage ofthe procedure. A vertical guide vane or rudder m is made fast to theupper side of the body at the tail end. It may be thus united by cementapplied to its lower edge, which is applied to the joined edges of thebody members.

Wings and guide vanes may likewise be made of balsa wood veneer, as iscommon in this art, but they may likewise be made of other suitablematerial and structure. When made of wood, the two wings may be cut froma single sheet and bent in the middle to form a dihedral angle. The sloti is suitably located and made long enough to permit adjustment of thewings forward and aft as may be necessary to give flying stability tothe plane.

The spreader I may be retained as a permanent brace for the molded bodyand also as a bed plate for the power plant and holder for the groundcarriage struts, and in such cases, the slots i and l are located sothat the wings and stabilizer will not interfere with the spreader.Figs. 1 and 4 show a form of spreader adapted for that purpose. This isa slender wedge of balsa wood, substantially thicker and stiffer thanthe other parts described. At the forward end there is secured to it alug 11 having a bearing aperture through which the propeller shaft 0passes. A hook p mounted on the spreader near its rear end serves as ananchorage for the motor spring, preferably constituted by one or morerubber bands q, which is also engaged with a hook on the inner end ofthe propeller shaft. The propeller r is secured to the outer end of theshaft.

In an alternative construction, shown in Fig. '7, the spreader isdispensed with after it has served its purpose in molding the body. Ahead block 12 is secured over the forward end of the body across theopening between the spread apart side pieces.

A thimble to which forms a bearing for the propeller shaft is removablyset into a central hole in the head block, and the motor band is ledthroughout the whole length of the body and passed over the stabilizervane it. Both the stabilizer vane and the thimbl-e w, with the propellershaft, may be withdrawn outwardly when necessary to substitute a newband for a broken one. In the case where the spreader supports the powerplant, it can be removed when renewal of power bands is needed.

These planes are provided with a landing gear, two forms of which arehere shown. That of Figs. 1 and 4 consists of wire struts s of which theinner end is bent sharply at right angles and clamped between the end ofthe spreader and a block u, which is secured to the under side of thespreader. Their outer ends are bent outward to form bearings for thewheels .1: and sharply upward outside of the wheels at u to retain thelatter on such bearings. shown in Figs. 5 and 8, landing gear struts sof thin strips of balsa wood are passed through forward extensions ofthe wing slots 1' and cemented to the inner wall of the body above suchslots. They reinforce those portions of the body to In the alternativeform which they are thus secured; and their attachment to the body holdsthem at the proper forward inclination and outward flare. A wheel axleis passed through their outer ends, on which Wheels are mounted in aknown manner.

The alternative constructions above described are not mutually exclusiveof one another in all particulars, but some of the features of each maybe used conjointly with features of the other. Thus it is not essentialthat the spreader be removed from the construction shown in Fig. 7. Itmay be retained permanently as in the case first described provided onlythat the wings and rear stabilizing vane k are located over or under it,or it is short enough to extend back only to the forward end of thestabilizing vane. Also the rear anchorage of the motor band q shown inFig. '7 may be used as well if the spreader is retained permanently asif it is removed. So also the landing gear struts of the type whichextend through the wing slots may be used with or without a permanentlyretained spreader, and in substitution for the wire struts shown inFigs. 1 and 4.

If desired, the various members of the plane may be reinforced by sheetsof thin tough paper, etc. cemented on one surface, or by stays orgussets applied to either the inner or the outer surface, at the ends ofthe slots or elsewhere that reinforcement may be desirable, these,however, being optional features previously known and not a part of thepresent invention.

What I claim and desire to secure by Letters Patent is:

1. The method of making a toy airplane body which consists in providingtwo body blanks or side pieces, securing said side pieces together sideby side at their edges, treating them to make them pliable, spreadingthem apart longitudinally between their connected edges to give the bodya convex hollow molded formation, and causing the body to become set insuch formation.

2. The method of making a toy airplane body which consists in providingtwo body blanks or side pieces, securing said side pieces together sideby side at their edges, treating them to make them pliable, inserting atapered spreader between the connected pieces at one end and passing thesame lengthwise between them, thereby expanding the body into moldedformation, and causing the material of the body members to become firmand nonpliable while the spreader remains in place between them.

3. The method of making a toy airplane body of the enclosed body typewhich comprises providing two like side pieces of wood veneer, placingsaid pieces side by side with their edges flush with one another,applying a cement solution to the adjacent longitudinal edges of thepieces and across their cleavage plane, steaming the united pieces afterthe cement has set, inserting a tapered spreader into one end of theconnected pieces and passing it toward the other end, and leaving thespreader in place While the pieces dry.

4. The method of making a toy airplane body of the enclosed body typewhich comprises providing two like sheets of balsa wood veneer havingoutlines simulating the profile of an airplane body, placing said sheetsside by side with their corresponding edges flush with one another,applying in fluid solution a cement which on setting is tough, flexibleand water-insoluble, to the adjacent longitudinal edges of the piecesand across the cleavage plane between them, allowing the cement solutionso applied to dry, steaming the connected pieces to soften them, passinga spreader between the pieces from one end toward the other end, therebyexpanding the body into molded formation, and drying the body with thespreader therein.

5. The method of making a toy airplane which comprises connecting fiatbody blanks together at their edges, making such connected blankspliable, inserting a spreader between the blanks and thereby bulging theintermediate portions between their connected edges away from oneanother, causing the body so formed to become nonpliable, and connectingwings and guiding vanes to said body.

6. The method of making a toy airplane which comprises connecting fiatbody blanks together at their edges, making such connected blankspliable, inserting a spreader between the blanks and thereby bulging theintermediate portions d between their connected edges away from oneanother, causing the body so formed to become non-pliable, and passing awing piece through the body through slots provided in the side pieces toreceive it.

'7. A toy airplane comprising a body made of two side pieces of balsawood veneer connected together in a flexibly hinged manner at theirupper and lower edges and bulged apart between said edges, a wingpassing through contained in slots in the side pieces thereof, and astabilizing vane secured to the tail end of the body.

8. A toy airplane body of hollow molded formation consisting of sidepieces connected together at their longitudinal edges by cement, and aspreader occupying the interior of the body in the widest portionthereof in supporting contact at its lateral edges with the innersurfaces of the body.

9. A toy airplane body consisting of two pieces of balsa wood incemented connection with each other at their longitudinal edges andbeing bulged apart from one another between their edges, and

a spreader within said body extending substantially throughout theentire length thereof in the widest part in supporting contact at itslateral edges with the inner surfaces of said side pieces.

10. The combination with an airplane body as set forth in claim 9, of apropeller and propeller shaft rotatably mounted on the forward end ofsaid spreader, and a power spring connected at one end to said propellershaft and anchored to the spreader at its other end at a point distantfrom the shaft.

11. A toy airplane consisting of a body constructed of balsa wood piecesconnected together at their opposite longitudinal edges in a flexiblyhinged manner and bulged apart from one ansaid body and other betweentheir edges, a wing passing through said body in slots formed in theside pieces, a stabilizing vane mounted on the tail end of the body, apropeller and propeller shaft rotatably supported at the forward end ofthe body, and a power spring coupled at one end to the propeller shaftand in anchored connected with the body at its opposite end distant fromthe propeller shaft.

12. A toy airplane consisting of a body constructed of two similar sidepieces connected together at their longitudinal edges by cement, beingbulged outwardly from one another between such edges, said side pieceshaving longitudinally extending slots, a wing passing through saidslots, and landing gear struts passing through the slots and cemented tothe inner surfaces of the body pieces above the slots.

13. A toy airplane body of hollow molded formation consisting of twoside pieces connected together at their longitudinal edges by cement, aspreader occupying the interior of the body extending in the front torear dimension thereof in the widest part, in supporting contact at itsedgeswith the inner surface of the body, landing gear struts passingthrough slots in the said side pieces each cemented to the inner surfaceof the adjacent side member above the slots, and a wing secured to saidbody.

14. A toy airplane consisting of a hollow molded body having outwardlybulged sides, a spreader within said body extending substantiallythroughout the entire length thereof in supporting contact at itslateral edges with the inner surfaces of said bulged sides, a propellershaft rot-atably supported on the forward end of said spreader andprotruding from the forward end of the body, a propeller secured to theprotruding portion of the shaft, a motor spring connected at one end tothe propeller shaft and in anchored connection with the spreader at apoint distant from the propeller shaft, a wing connected to the bodyintermediate its ends, and stabilizing members connected to the body atthe rear end thereof.

15. A toy airplane consisting of a hollow body having outwardly bulgedsides, wings and stabilizer vanes connected to said body, a spreaderoccupying the interior of the body in the widest portion thereof and insupporting contact at its lateral edges with the inner surfaces of thebody, and a power plant consisting of a propeller shaft, a propellersecured to the shaft, and a motor spring all mounted on said spreader,the propeller being located outside of the forward end of the body andthe spreader being removable with the power plant from the body, wherebyto permit repairs of the power plant.

THOMAS D. WILDON.

